Chemical reaction in which heat is
evolved?

1 Answer

Answer :

Exothermic reaction

Related questions

Description : Under what condition, the heat evolved or absorbed in a reaction is equal to its free energy change?

Last Answer : Ans. As ΔG = ΔH – TΔS. Thus, ΔG = ΔH only when either the reaction is carried out at 0^0 K or the reaction is not accompanied by any entropy change, i.e., ΔS = 0

Description : Under what condition, the heat evolved/absorbed in a reaction is equal to its free energy change?

Last Answer : Ans. In ∆G = ∆H – T. ∆S, when reaction is carried out at 0 K or ∆S = 0, then ∆G = ∆H.

Description : For the irreversible reaction, Ca+ 2C = Ca C2, Δ H°298 = - 60000 J . mole-1. If a system initially containing 2 moles of calcium, 3 moles of carbon and 1 mole of calcium carbide is allowed to react to completion, the heat evolved ... will be (A) 30,000 J (B) 60,000 J (C) 90,000 J (D) 2,40,000 J

Last Answer : (C) 90,000 J

Description : A student dropped few pieces of marble in dilute hydrochloric acid contained in a test tube. The evolved gas was then passed through lime water. What change would be observed in lime water? Write balanced chemical equation for both the change observed?

Last Answer : Answer. When dilute HCl is added to marble which is calcium carbonate, it forms calcium chloride, water and carbon dioxide. The chemical equation for the reaction is as follows: CaCO3 + 2HCl → CaCl2 + H2O ... reaction between lime water and carbon dioxide is as follows: Ca(OH)2 + CO2 → CaCO3 + H2O

Description : Which one among the following substances evolved heat when dissolved in water? (1) Glucose (2) Fructose (3) Quick lime (4) Salt peter

Last Answer : (3) Quick lime Explanation: Quicklime is a widely used chemical compound. It is a white, caustic, alkaline, crystalline solid at room temperature. When limestone is heated, at about 1000° C it undergoes thermal decomposition.

Description : Heat requirement for decomposition of a compound into its elements is __________ that is evolved during the formation of that compound from its elements. (A) The same (B) Less than (C) Greater than (D) Different than

Last Answer : (A) The same

Description : Heat evolved/absorbed during conversion of a substance from one allotropic form to another is termed as the heat of (A) Fusion (B) Vaporisation (C) Transition (D) None of these

Last Answer : (C) Transition

Description : The oxygen evolved during photosynthesis comes from water molecules . Which one of the following pairs of elemnets is involved in this reaction ?

Last Answer : The oxygen evolved during photosynthesis comes from water molecules . Which one of the ... Manganese and Potassium D. Magnesium and Molybdenum

Description : The oxygen evolved during photosynthesis, comes from water molecules. Which one of the following pairs of elements is involved in this reaction? (a) Magnesium and Molybdenum (b) Magnesium and Chlorine (c) Manganese and Chlorine (d) Manganese and Potassium

Last Answer : (c) Manganese and Chlorine

Description : Chemical reaction in which heat is ab- sorbed?

Last Answer : Endothermic reaction

Description : Chemical reaction in which heat is re- leased?

Last Answer : Exothermic reaction

Description : A chemical reaction in which there is absorption of heat is called

Last Answer : endothermic reaction.

Description : A chemical reaction in which heat is liberated is called

Last Answer : exothermic reaction.

Description : What is a chemical reaction that releases energy by light or heat?

Last Answer : Need answer

Description : What is the best term to describe a chemical reaction that absorbs heat energy?

Last Answer : What is the answer ?

Description : What is chemical reaction that gives off heat called?

Last Answer : Exothermic reactions give off heat.

Description : An enzyme promotes a chemical reaction by (A) Lowering the energy of activation (B) Causing the release of heat which acts as a primer (C) Increasing molecular motion (D) Changing the free energy difference between substrate and product

Last Answer : Answer : A

Description : Analogy between mass and heat transfer is not applicable in case of (A) Same velocity profile or equal eddy diffusivities (B) Thermal or pressure mass diffusion (C) Viscous heating or chemical reaction (D) Both (B) and (C)

Last Answer : (D) Both (B) and (C)

Description : The Graetz number is concerned with the (A) Mass transfer between a gas and a liquid (B) Absorption with chemical reaction (C) Heat transfer in turbulent flow (D) Heat transfer in laminar flow

Last Answer : (D) Heat transfer in laminar flow

Description : The role of a catalyst in a chemical reaction is to change the (A) Equilibrium constant (B) Activation energy (C) Final products (D) Heat of reaction

Last Answer : (B) Activation energy

Description : Catalytic action in a catalytic chemical reaction follows from the ability of catalyst to change the (A) Activation energy (B) Equilibrium constant (C) Heat of reaction (D) None of these

Last Answer : (A) Activation energy

Description : The energy of activation of a chemical reaction: (A) Is same as heat of reaction at constant pressure (B) Is the minimum energy which the molecules must have before the reaction can take place (C) Varies as fifth power of the temperature (D) Both (B) and (C)

Last Answer : (B) Is the minimum energy which the molecules must have before the reaction can take place

Description : Pick out the correct statement. (A) A chemical reaction accompanied by absorption of heat is called an exothermic reaction (B) A chemical reaction accompanied by evolution of heat is called an ... does not change on changing the concentration units (D) Chemical equilibrium state is dynamic in nature

Last Answer : (C) The rate constant for a first order reaction does not change on changing the concentration units

Description : The catalyst in a first order chemical reaction changes the (A) Equilibrium constant (B) Activation energy (C) Heat of formation of the product (D) Heat of reaction

Last Answer : (B) Activation energy

Description : If the molar heat capacities (Cp or Cv) of the reactants and products of a chemical reaction are identical, then, with the increase in temperature, the heat of reaction will (A) Increase (B) Decrease (C) Remain unaltered (D) Increase or decrease; depends on the particular reaction

Last Answer : (C) Remain unaltered

Description : When an isolated thermodynamic system executes a process, (A) Work is done (B) Heat transfer takes place (C) Mass flow occurs across the boundary of the system (D) No chemical reaction takes place within the system

Last Answer : D) No chemical reaction takes place within the system

Description : Pick up the incorrect statement from the following: (A) The degree of grinding of cement, is called fineness (B) The process of changing cement paste into hard mass, is known as setting of ... (D) The heat generated during chemical reaction of cement with water, is known as heat of hydration

Last Answer : Answer: Option C

Description : Which of the following events is heat exchange involved?  a. when there is a phase change  b. when there is a chemical reaction  c. when the gas expands adiabatically  d. when there is difference in temperature

Last Answer : when the gas expands adiabatically

Description : The browning reaction due to chemical reaction between an amino acid and a reducing sugar, usually requiring heat is called as _____: a. Dextrinization b. Maillard reaction c. Scorching d. Caramelization

Last Answer : b. Maillard reaction

Description : What happens when a catalyst is added to a system at equilibrium? A The reaction follows an alternative pathway of lower activation energy. B The heat of reaction decreases. C The potential ... decreases. D The potential energy of the products decreases. E The rate of chemical reaction decreases.

Last Answer : A The reaction follows an alternative pathway of lower activation energy.

Description : Is there a theory that suggests pale skinned people's brains have evolved to desire control of their territory more so than other humans?

Last Answer : It doesn’t sound outrageous. I mean god its gotta be something, right? We’re such killers. But maybe that’s just man in general….?

Description : When zinc reacts with hydrochloric acid, the gas evolved is (a) Oxygen (b) Hydrogen (c) Chlorine (d) None of these

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Description : The most evolved group of plants are

Last Answer : angiosperms.

Description : Point out any two characteristics that support the idea that Platypus is more evolved than tortoise.

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Description : An aluminium strip is kept immersed in a freshly prepared ferrous sulphate solution taken in a test tube, the change observed is that a) Green solution slowly turns brown b) Lower end of the test ... c)A colourless gas with smell of burning sulphur is evolved c)Light green solution changes to blue

Last Answer : a) Green solution slowly turns brown

Description : Salt A commonly used in bakery products on heating gets converted into another salt B which itself is used for removal the hardness of water and a gas C is evolved. The gas C when passed through lime water ,turns it ... © A is baking soda ,B is washing soda and C is carbon dioxide (d) both a and c

Last Answer : (d) both a and c

Description : Zinc granules on treating with an acid X, form the zinc sulphate (ZnSO4) salt along with the evolution of a gas Y which burns with a pop sound when brought near to a burning candle. Identify the acid X and ... (c). X- Sulphuric acid and Y- Hydrogen gas (d). X- Hydrochloric acid and Y- Hydrogen gas

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Description : Do humans that have evolved in dry places, like Africa and the Middle East, have more water-efficient bodies?

Last Answer : All humans evolved in Africa.

Description : How has your palate evolved?

Last Answer : answer:I used to take my morning coffee with milk, until I read that the hormones in milk are bad for your skin, so for the last few weeks I’ve been drinking coffee with nothing added. I now believe that this is the superior way to drink coffee. Plus my skin looks better now too so win/win.

Description : Do you think its possible that life could have evolved on other planets; in a similar manner to Earth?

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Description : What is the correct pronunciation of the word "eBay", and how has the name (not the company) evolved?

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Description : Human Females are unique among all mammalians. Why do you think the ability to hide fertile time periods evolved in human women?

Last Answer : Ummm, what?

Description : A question about superman: How can a species have evolved to have superpowers that require a type of star that this species did not evolve under?

Last Answer : Heavy planets core…. like uranium. Sort of like exercising on the top of a mountain and then competing in sea level, that would give you an edge.

Description : Politically incorrect Q: If different racial charactistics evolved as response to different climates, why aren't Alaskan natives or oriental peoples from the north or indigineous peoples of Australia and South Africa as pale as northern Europeans?

Last Answer : According to this article, it has to do with dietary differences. People with diets high in vitamin D don’t need the sun to help them synthesize it. That’s the explanation offered for the Inuit, at least. I don’t know how broadly it might apply.

Description : How would mankind have evolved if dinosaurs didn't die off?

Last Answer : Running.

Description : Is vegetarianism a morally and spiritually evolved practice?

Last Answer : No. Because depending on the type of vegetarianism, they can still eat eggs, fish and crabs, and they are just as much animals as cows, pigs, sheep, chicken and dogs. Veganism is.

Description : What is our most primitive emotion, and have we evolved beyond it?

Last Answer : It seems like survival would be the #1 priority, so maybe fear and defense would be somewhere near the top of the emotions list. As for whether human emotions have changed over time, I doubt it. As far ... impact on how we act, at least in public, but the basic emotions still seem to stick around.

Description : How much has your style evolved over the years?

Last Answer : Oh man! My style has changed like crazy. Before I was interested in fashion but I didn't know how to look good on a budget. Then I started watching videos on Youtube and then it turned into me ... seeing other people how they dress got me inspired to keep track of how I dress and what I dress.

Description : How have species evolved from a single cell organism?

Last Answer : Time. Around 3.8 billion years.

Description : Events in history that show how independence has evolved throughout society?

Last Answer : I think we’ve always been dependant on “society”. That is what makes us soooo successful as a species. Specialization opened up more opportunities for inventing and discovery. Without it we would still be wandering around hunting and gathering for our nutrition.